RM6203 High Performance Current Mode PWM Switching Power Supply controller DESCRIPTION The RM6203 is a current mode PWM switching power supply controller that specifically designed for AC/DC converter with high performance versus cost ratio. It provides continuous output power up to 12W in the broad voltage range of 85V – 265V.Its optimized and highly reasonable circuit design has made it possible to minimize the total cost of the product. This power supply controller could be used in typical flyback circuit topology to constitute simple AC/DC converter. The internal initiating circuit of RM6203 has been designed with a unique means of current sink to complete the startup using the amplifying function of the power switching tube. This will significantly reduce the power consumption of the start-up resistor; and when the output power becomes smaller, RM6203 will automatically lower its operating frequency to enable very low standby power consumption. When the power tube stops, the internal circuit will turn the power tube reverse bias to greatly raise the voltage resistant capacity of OC pin. This will ensure the safety of the power tube. The internal design of the RM6203 is also provided with over-load and saturation preventive function capable of preventing disorders such as overload, transformer saturation and output short-circuit, so as to increase the reliability of the power supply. A voltage reference of 2.5V is also integrated in the RM6203 to provide accurate power supply to the clock circuit, and the clock frequency may be set by external timing capacitance. Presently, standard DIP8 package and environmental friendly lead-free package in compliance with European standard can be supplied. FEATURES ■ Built-in 700V high voltage power switching tube with minimal external parts count ■ Latched PWM and pulse-by-pulse current limiting inspection ■ Reduced frequency at low output with standby power consumption below 0.25W ■ Built-in slope and feedback compensation function ■ Separate upper limit current inspection controller to handle timely the over-current and overload of the controller ■ Turn off periodic bias output of the emitter to improve the voltage resistance of the power tube ■ Built-in thermal protective circuit ■ Complete start-up using amplification of the switching power tube to reduce the power consumption of the start-up resistor more than ten times ■ Automatic VCC over-voltage limit ■ Broad voltage output power up to 5W and narrow voltage output power up to 8W Applications ■ Power Adaptors(traveling chargers ,stand-alone power set) ■ Internal power supply for Energy-Saving Appliances (such as electromagnetic oven, microwave oven and etc.) www.reactor-micro.com 1 RM6203 TYPICAL APPLICATION PACKAGE INFORMATION TOP VIEW DIP-8 PIN FUNCTIONS Pin 1 2 3 4 5 6 7、8 Symbol OB VCC GND CT FB IS OC Function Description Base Pin of the Power Tube.(Enabling c […]